GUANGZHOU - Four people died and five others were injured when a fire brigade office under construction collapsed Saturday in Guangzhou, capital of South China's Guangdong province.

Sixteen people were working at the site when the building toppled, in the Haizhu district at midday, the municipal fire prevention bureau said. 

It said seven workers were buried under the rubble and two others were injured.

Four of the missing workers were dead when rescuers retrieved them at 4:30 pm The other three were seriously injured. All the injured workers were taken to hospital.

Police have launched an investigation and detained the site manager for questioning.